I'm using XAMPP for linux, installed in CLI, on Ubuntu Server 16.04 LTS, after installing and uploading my pages done on XAMPP on Windows , I tested simple thing. if i put URL/myfile.php it gaves me weird answer. Where I should find problem causing me this toubles ?

That *should* switch off weird messages for weird URLs on Linux (i am not sure about that, but it looks Ok, or not?!). As we dont know, which URL you entered (or did you enter "URL"?), i have no better clue.

Next, proceed to /opt/lampp/etc and edit httpd.conf and try to insert:

weird_messages = Off

hopefully this prevents Apache to give "weird messages". If all this works, you are Ok and upset, if not, you should think about providing us the "weird" message, as we have no idea, what is meant by that. Good luck!